Pollen is a fine to coarse powder consisting of microgametophytes (=pollen grains), which produce the male gametes (sperm cells) of seed plants. A hard coat covering the pollen grain protects the sperm cells during the process of their movement between the stamens of the flower to the pistil of the next flower.
Pollen grain morphology is breathtakingly divers. Orchids produce a pollinium, which consists of thousands of pollen grains, packed in dozens of massulae. The pollinium is attached to pollinators, which are often attracted e.g. by beautiful colors.